Guidance apparatus for supporting a device in close proximity to the inner wall of a tapered stack



July 29, 1969 o. DONALDSON GUIDANCE APPARATUS FUR SUPPORTING A DEVICE IN CLOSE PROXIMITY TO THE INNER WALL OF A TAPERED STACK Filed Feb. 6. 1968 INVENTOR Or/in Donaldson United States Patent Office GUIDANCE APPARATUS FOR SUPPORTING A DE- VICE IN CLOSE PROXIMITY TO THE INNER WALL OF A TAPERED STACK Orlin Donaldson, Bethlehem, Pa., assignor to Bethlehem Steel Corporation, a corporation of Delaware Filed Feb. 6, 1968, Ser. No. 703,361 Int. Cl. B66b 9/00; G03b 19/00 US. Cl. 187-1 3 Claims ABSTRACT OF THE DISCLOSURE Background of the invention This invention relates generally to guidance apparatus for supporting a device in close proximity to the inner wall of a tapered stack. More specifically, this invention relates to guidance apparatus for supporting a camera vehicle in close proximity to the inner Wall of a tapered stack to permit photographs of said wall to be taken.

Other devices for supporting camera vehicles in tapered stacks for photographic purposes have been cumbersome and expensive, and otherwise not entirely satisfactory for a number of reasons. One such arrangement is shown in Blast Furnace and Steel Plant, June 1966, pp. 510-511. This arrangement employs a winch and a standoff pole, mounted on opposite sides of the stack top. Apparently no means are provided for maintaining the camera vehicle in close proximity to the stack wall.

The present invention represents a considerable improvement over prior art arrangements in that it permits the use of a single lowering cable and keeps the camera vehicle steady and in close proximity to the stack wall at all times when the device is in operation.

Summary of the invention One of the objects of this invention is to provide guidance apparatus for supporting a device in close proximity to the inner wall of a tapered stack.

Another of the objects of this invention is to provide guidance apparatus for supporting a camera vehicle in close proximity to the inner wall of a tapered stack for photographic purposes.

I have discovered that the foregoing objects can be attained by hinging a thrust rod for rotation in a vertical plane to the midpoint of a wheeled beam supporting the device or camera vehicle, the free end of the thrust rod engaging the wall of the stack above and opposite the wheels of the wheeled beam, whereby gravitational forces on the thrust rod resulting in a component urging the wheels of the wheeled beam into continuous engagement with the stack wall, thereby maintaining the device or camera vehicle in continuous proximity to the stack wall.

Brief description of the drawing FIGURE 1 represents a view in elevation of the present invention in operative position within a tapered stack.

FIGURE 2 represents a view in plan of the present invention in operative position within the tapered stack.

FIGURE 3 represents an enlarged perspective view of the present invention.

Patented July 29, 1969 Description of the preferred embodiment In the preferred embodiment, the present invention is employed for the purpose of supporting a camera vehicle 1 in close proximity to the inner wall 2 of a tapered stack 3.

The details of the camera vehicle 1 are not important although, for a full understanding of the environment of the present invention, it will be noted that camera vehicle 1 comprises an elongated heat insulated housing 4 enclosing a camera (not shown), and having a heat reflective and heat resistant glass covered aperture 5 through which the camera may photograph portions of inner wall 2. Suitable lighting means (not shown) may be mounted to housing 4.

Beam 6 supports camera vehicle 1 by means of cable 7. Wheels 8 are rotatably mounted to the ends of beam 6, preferably obliquely and at such an angle that the said wheels 8 are perpendicular to those portions of inner wall 2 contacted by the wheels 8.

A substantially rigid thrust rod 9, of length greater than the maximum inside horizontal dimensions of the stack 3, in the area to be photographed by the camera, is pivotally mounted to the center of beam 6, between brackets 10, so as to be capable of rotation in a vertical plane and restrained against any substantial movement in other directions.

Beam 6, with camera vehicle 1 suspended therefrom, is raised and lowered in stack 3 by means of cable 11 secured to the center of beam .6. Cable 11 and cable 7 may be parts of the same cable extended through and clamped to collar 12 in beam 6.

In operation, cable 11 is paid out to lower beam 6, and the camera vehicle 1 suspended therefrom, down the stack 3, with wheels 8 engaging and rolling down walls 2 of the said stack, and with the free end 13 of thrust rod 9 sliding down the opposite side of stack 3 and always at a higher elevation within stack 3 than the pivoted end 14 of said thrust rod 9. Thrust rod 9 has sufficient mass to produce a force component urging the beam 6 into continuous engagement, through wheels 8, with the wall 2 of stack 3. In this manner, camera vehicle 1 will always be in close proximity to Wall 2, and satisfactory pictures thereof taken.

When it is desired to retrieve beam 6 and the camera vehicle 1 suspended therefrom, the free end 13 of thrust rod 9 may be raised clear of wall 2 by means of cable 15, and cable 11 taken in to remove beam 6 and camera vehicle 1 from stack 3.

Alternatively, and in lieu of cable 15, and in view of the fact that thrust rod 9 may be a fairly slender length of pipe, beam 6 and camera vehicle 1 may be retrieved from stack 3 simply by pulling up on cable 11 with such force as to bend or collapse thrust rod 9, after which the beam 6 and camera vehicle 1 can be removed simply by further taking in of cable 11.

I claim:

1. In association with first and second spaced opposed walls, said first wall being inclined downwardly and away from said second wall, apparatus for lowering a device between said first and second walls in continuous proximity to said first wall, said apparatus comprising:

(a) a horizontal member,

(b) means adapted to mount said device to the midpoint of said horizontal member,

(c) a pair of wheels rotatably mounted to opposite ends of said horizontal member and adapted to rollably engage said first wall,

(d) an elongated substantially rigid member having a first end and a second end, said elongated rigid member being of length greater than the maximum horizontal distance between said first and second walls,

3 4 (e) means pivotally mounting the first end of said elonzontal member obliquely to the longitudinal axis of gated rigid member to the midpoint of said horizontal said horizontal member, whereby each wheel is permember for rotation in a vertical plane perpendicular pendicular to the portion of the inner wall engaged to the longitudinal axis of said horizontal member, by said wheel.

(f) the second end of said elongated rigid member be- 3. Apparatus as in claim 1, further comprising:

ing adapted to slidably engage the second wall at an 5 (h) said elongated rigid member being restrained elevation above the elevation of the first end of said against any substantial movement relative to said elongated rigid member, said elongated rigid member horizontal member in directions other than a vertical having suflicient mass to urge said wheels against plane. said first wall,

(g) whereby said elongated rigid member exerts a con- References Cited tinuous thrust against said horizontal member in a UNITED STATES PATENTS direction towards said first wall to continuously main- 2,667,109 1/1954 pi 95 11 tain said wheels in rolling engagement with said first 3,279,0 5 1 19 Reinhart 95 11 wall.

2. Apparatus as in claim 1, said first and second walls EVON C. BLUNK, Primary Examiner being opposite sides of the inner wall of a tapered stack of circular cross-section and of diameter decreasing in HORNSBY Asslstant Exammer an upward direction, said apparatus further compris- Us CL ing:

(h) said wheels being rotatably mounted to said hori- 104-438 

